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"""Integration with Python standard library module urllib2: OpenerDirector
class.
Copyright 2004-2006 John J Lee <jjl@pobox.com>
This code is free software; you can redistribute it and/or modify it
under the terms of the BSD or ZPL 2.1 licenses (see the file
COPYING.txt included with the distribution).
"""
import os, urllib2, bisect, httplib, types, tempfile
try:
import threading as _threading
except ImportError:
import dummy_threading as _threading
try:
set
except NameError:
import sets
set = sets.Set
import _file
import _http
from _request import Request
import _response
import _rfc3986
import _sockettimeout
import _upgrade
from _util import isstringlike
class ContentTooShortError(urllib2.URLError):
def __init__(self, reason, result):
urllib2.URLError.__init__(self, reason)
self.result = result
def set_request_attr(req, name, value, default):
try:
getattr(req, name)
except AttributeError:
setattr(req, name, default)
if value is not default:
setattr(req, name, value)
class OpenerDirector(urllib2.OpenerDirector):
def __init__(self):
urllib2.OpenerDirector.__init__(self)
# really none of these are (sanely) public -- the lack of initial
# underscore on some is just due to following urllib2
self.process_response = {}
self.process_request = {}
self._any_request = {}
self._any_response = {}
self._handler_index_valid = True
self._tempfiles = []
def add_handler(self, handler):
if handler in self.handlers:
return
# XXX why does self.handlers need to be sorted?
bisect.insort(self.handlers, handler)
handler.add_parent(self)
self._handler_index_valid = False
def _maybe_reindex_handlers(self):
if self._handler_index_valid:
return
handle_error = {}
handle_open = {}
process_request = {}
process_response = {}
any_request = set()
any_response = set()
unwanted = []
for handler in self.handlers:
added = False
for meth in dir(handler):
if meth in ["redirect_request", "do_open", "proxy_open"]:
# oops, coincidental match
continue
if meth == "any_request":
any_request.add(handler)
added = True
continue
elif meth == "any_response":
any_response.add(handler)
added = True
continue
ii = meth.find("_")
scheme = meth[:ii]
condition = meth[ii+1:]
if condition.startswith("error"):
jj = meth[ii+1:].find("_") + ii + 1
kind = meth[jj+1:]
try:
kind = int(kind)
except ValueError:
pass
lookup = handle_error.setdefault(scheme, {})
elif condition == "open":
kind = scheme
lookup = handle_open
elif condition == "request":
kind = scheme
lookup = process_request
elif condition == "response":
kind = scheme
lookup = process_response
else:
continue
lookup.setdefault(kind, set()).add(handler)
added = True
if not added:
unwanted.append(handler)
for handler in unwanted:
self.handlers.remove(handler)
# sort indexed methods
# XXX could be cleaned up
for lookup in [process_request, process_response]:
for scheme, handlers in lookup.iteritems():
lookup[scheme] = handlers
for scheme, lookup in handle_error.iteritems():
for code, handlers in lookup.iteritems():
handlers = list(handlers)
handlers.sort()
lookup[code] = handlers
for scheme, handlers in handle_open.iteritems():
handlers = list(handlers)
handlers.sort()
handle_open[scheme] = handlers
# cache the indexes
self.handle_error = handle_error
self.handle_open = handle_open
self.process_request = process_request
self.process_response = process_response
self._any_request = any_request
self._any_response = any_response
def _request(self, url_or_req, data, visit,
timeout=_sockettimeout._GLOBAL_DEFAULT_TIMEOUT):
if isstringlike(url_or_req):
req = Request(url_or_req, data, visit=visit, timeout=timeout)
else:
# already a urllib2.Request or mechanize.Request instance
req = url_or_req
if data is not None:
req.add_data(data)
# XXX yuck
set_request_attr(req, "visit", visit, None)
set_request_attr(req, "timeout", timeout,
_sockettimeout._GLOBAL_DEFAULT_TIMEOUT)
return req
def open(self, fullurl, data=None,
timeout=_sockettimeout._GLOBAL_DEFAULT_TIMEOUT):
req = self._request(fullurl, data, None, timeout)
req_scheme = req.get_type()
self._maybe_reindex_handlers()
# pre-process request
# XXX should we allow a Processor to change the URL scheme
# of the request?
request_processors = set(self.process_request.get(req_scheme, []))
request_processors.update(self._any_request)
request_processors = list(request_processors)
request_processors.sort()
for processor in request_processors:
for meth_name in ["any_request", req_scheme+"_request"]:
meth = getattr(processor, meth_name, None)
if meth:
req = meth(req)
# In Python >= 2.4, .open() supports processors already, so we must
# call ._open() instead.
urlopen = getattr(urllib2.OpenerDirector, "_open",
urllib2.OpenerDirector.open)
response = urlopen(self, req, data)
# post-process response
response_processors = set(self.process_response.get(req_scheme, []))
response_processors.update(self._any_response)
response_processors = list(response_processors)
response_processors.sort()
for processor in response_processors:
for meth_name in ["any_response", req_scheme+"_response"]:
meth = getattr(processor, meth_name, None)
if meth:
response = meth(req, response)
return response
def error(self, proto, *args):
if proto in ['http', 'https']:
# XXX http[s] protocols are special-cased
dict = self.handle_error['http'] # https is not different than http
proto = args[2] # YUCK!
meth_name = 'http_error_%s' % proto
http_err = 1
orig_args = args
else:
dict = self.handle_error
meth_name = proto + '_error'
http_err = 0
args = (dict, proto, meth_name) + args
result = apply(self._call_chain, args)
if result:
return result
if http_err:
args = (dict, 'default', 'http_error_default') + orig_args
return apply(self._call_chain, args)
BLOCK_SIZE = 1024*8
def retrieve(self, fullurl, filename=None, reporthook=None, data=None,
timeout=_sockettimeout._GLOBAL_DEFAULT_TIMEOUT):
"""Returns (filename, headers).
For remote objects, the default filename will refer to a temporary
file. Temporary files are removed when the OpenerDirector.close()
method is called.
For file: URLs, at present the returned filename is None. This may
change in future.
If the actual number of bytes read is less than indicated by the
Content-Length header, raises ContentTooShortError (a URLError
subclass). The exception's .result attribute contains the (filename,
headers) that would have been returned.
"""
req = self._request(fullurl, data, False, timeout)
scheme = req.get_type()
fp = self.open(req)
headers = fp.info()
if filename is None and scheme == 'file':
# XXX req.get_selector() seems broken here, return None,
# pending sanity :-/
return None, headers
#return urllib.url2pathname(req.get_selector()), headers
if filename:
tfp = open(filename, 'wb')
else:
path = _rfc3986.urlsplit(req.get_full_url())[2]
suffix = os.path.splitext(path)[1]
fd, filename = tempfile.mkstemp(suffix)
self._tempfiles.append(filename)
tfp = os.fdopen(fd, 'wb')
result = filename, headers
bs = self.BLOCK_SIZE
size = -1
read = 0
blocknum = 0
if reporthook:
if "content-length" in headers:
size = int(headers["Content-Length"])
reporthook(blocknum, bs, size)
while 1:
block = fp.read(bs)
if block == "":
break
read += len(block)
tfp.write(block)
blocknum += 1
if reporthook:
reporthook(blocknum, bs, size)
fp.close()
tfp.close()
del fp
del tfp
# raise exception if actual size does not match content-length header
if size >= 0 and read < size:
raise ContentTooShortError(
"retrieval incomplete: "
"got only %i out of %i bytes" % (read, size),
result
)
return result
def close(self):
urllib2.OpenerDirector.close(self)
# make it very obvious this object is no longer supposed to be used
self.open = self.error = self.retrieve = self.add_handler = None
if self._tempfiles:
for filename in self._tempfiles:
try:
os.unlink(filename)
except OSError:
pass
del self._tempfiles[:]
def wrapped_open(urlopen, process_response_object, fullurl, data=None,
timeout=_sockettimeout._GLOBAL_DEFAULT_TIMEOUT):
success = True
try:
response = urlopen(fullurl, data, timeout)
except urllib2.HTTPError, error:
success = False
if error.fp is None: # not a response
raise
response = error
if response is not None:
response = process_response_object(response)
if not success:
raise response
return response
class ResponseProcessingOpener(OpenerDirector):
def open(self, fullurl, data=None,
timeout=_sockettimeout._GLOBAL_DEFAULT_TIMEOUT):
def bound_open(fullurl, data=None,
timeout=_sockettimeout._GLOBAL_DEFAULT_TIMEOUT):
return OpenerDirector.open(self, fullurl, data, timeout)
return wrapped_open(
bound_open, self.process_response_object, fullurl, data, timeout)
def process_response_object(self, response):
return response
class SeekableResponseOpener(ResponseProcessingOpener):
def process_response_object(self, response):
return _response.seek_wrapped_response(response)
class OpenerFactory:
"""This class's interface is quite likely to change."""
default_classes = [
# handlers
urllib2.ProxyHandler,
urllib2.UnknownHandler,
_http.HTTPHandler, # derived from new AbstractHTTPHandler
_http.HTTPDefaultErrorHandler,
_http.HTTPRedirectHandler, # bugfixed
urllib2.FTPHandler,
_file.FileHandler,
# processors
_upgrade.HTTPRequestUpgradeProcessor,
_http.HTTPCookieProcessor,
_http.HTTPErrorProcessor,
]
if hasattr(httplib, 'HTTPS'):
default_classes.append(_http.HTTPSHandler)
handlers = []
replacement_handlers = []
def __init__(self, klass=OpenerDirector):
self.klass = klass
def build_opener(self, *handlers):
"""Create an opener object from a list of handlers and processors.
The opener will use several default handlers and processors, including
support for HTTP and FTP.
If any of the handlers passed as arguments are subclasses of the
default handlers, the default handlers will not be used.
"""
opener = self.klass()
default_classes = list(self.default_classes)
skip = []
for klass in default_classes:
for check in handlers:
if type(check) == types.ClassType:
if issubclass(check, klass):
skip.append(klass)
elif type(check) == types.InstanceType:
if isinstance(check, klass):
skip.append(klass)
for klass in skip:
default_classes.remove(klass)
for klass in default_classes:
opener.add_handler(klass())
for h in handlers:
if type(h) == types.ClassType:
h = h()
opener.add_handler(h)
return opener
build_opener = OpenerFactory().build_opener
_opener = None
urlopen_lock = _threading.Lock()
def urlopen(url, data=None, timeout=_sockettimeout._GLOBAL_DEFAULT_TIMEOUT):
global _opener
if _opener is None:
urlopen_lock.acquire()
try:
if _opener is None:
_opener = build_opener()
finally:
urlopen_lock.release()
return _opener.open(url, data, timeout)
def urlretrieve(url, filename=None, reporthook=None, data=None,
timeout=_sockettimeout._GLOBAL_DEFAULT_TIMEOUT):
global _opener
if _opener is None:
urlopen_lock.acquire()
try:
if _opener is None:
_opener = build_opener()
finally:
urlopen_lock.release()
return _opener.retrieve(url, filename, reporthook, data, timeout)
def install_opener(opener):
global _opener
_opener = opener
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